From DE 41 01 290 a heating element is known in which a multitude of heating conductors which are spaced apart and do not touch each other are arranged between two electrodes. One disadvantage of this type of design is that when there is a break in a heating conductor, the part of the base surface to be heated that is coated by this heating conductor can no longer be heated. It is particularly undesirable if the heating element is to be sewn in, because a large number of heating conductors can be damaged by the sewing needle.
From U.S. Pat. No. 6,531,687, a heating element is known in which a multitude of heating conductors connected with one another are laid between two electrodes. When there is a break in a heating conductor, the cross-linking of the heating conductors with one another leads to a deviation of the current around the location of the break. Consequently, despite a break in a heating conductor, this heating element will continue to heat the base surface to be heated in a substantially uniform manner. However, a difficulty arises in that when an electrode breaks, unwanted concentrations of current can occur at the location of the break in the electrode precisely due to the cross-linking of the heating conductors with one another. As a result, overheating or “hot spots” can occur in this area.